This commit adds a TOML configuration option to swarm. It reuses
the TOML configuration structure used in geth with swarm
customized items.
The commit:
* Adds a "dumpconfig" command to the swarm executable which
allows printing the (default) configuration to stdout, which
then can be redirected to a file in order to customize it.
* Adds a "--config <file>" option to the swarm executable which will
allow to load a configuration file in TOML format from the
specified location in order to initialize the Swarm node The
override priorities are like follows: environment variables
override command line arguments override config file override
default config.
Previously, NewManifest was asynchronous so subsequent code which tried
to use the returned manifest could error as the manifest was not yet
persisted.
The previous attempt to use --ethapi as a fallback if --ens-api is not
set does not work because --ens-api has a default value, and also
setting --ens-api to "" is the suggested way to disable ENS lookups.
Signed-off-by: Lewis Marshall <lewis@lmars.net>
